Problem 38
Create a stem-and-leaf display for these horsepowers of autos reviewed by Consumer Reports one year, and describe the distribution: \(\begin{array}{rrrrr} 155 & 103 & 130 & 80 & 65 \\ 142 & 125 & 129 & 71 & 69 \\ 125 & 115 & 138 & 68 & 78 \\ 150 & 133 & 135 & 90 & 97 \\ 68 & 105 & 88 & 115 & 110 \\ 95 & 85 & 109 & 115 & 71 \\ 97 & 110 & 65 & 90 & \\ 75 & 120 & 80 & 70 & \end{array}\)
Problem 41
Two researchers measured the pH (a scale on which a value of 7 is neutral and values below 7 are acidic) of water collected from rain and snow over a 6-month period in Allegheny County, PA. Describe their data with a graph and a few sentences: \(\begin{array}{lllllllll}4.57 & 5.62 & 4.12 & 5.29 & 4.64 & 4.31 & 4.30 & 4.39 & 4.45 \\ 5.67 & 4.39 & 4.52 & 4.26 & 4.26 & 4.40 & 5.78 & 4.73 & 4.56 \\\ 5.08 & 4.41 & 4.12 & 5.51 & 4.82 & 4.63 & 4.29 & 4.60 & \end{array}\)
Problem 45
Holes-R-Us, an Internet company that sells piercing jewelry, keeps transaction records on its sales. At a recent sales meeting, one of the staff presented a histogram of the zip codes of the last 500 customers, so that the staff might understand where sales are coming from. Comment on the usefulness and appropriateness of the display.
Problem 50
A report from the U.S. Department of Justice (www.ojp.usdoj.gov/bjs/) reported the percent changes in federal prison populations in 21 northeastern and midwestern states during 2005. Using appropriate graphical displays and summary statistics, write a report on the changes in prison populations. \(\begin{array}{l|c|l|c} \text { State } & \begin{array}{l} \text { Percent } \\ \text { Change } \end{array} & \text { State } & \begin{array}{c} \text { Percent } \\ \text { Change } \end{array} \\ \hline \text { Connecticut } & -0.3 & \text { Iowa } & 2.5 \\ \text { Maine } & 0.0 & \text { Kansas } & 1.1 \\ \text { Massachusetts } & 5.5 & \text { Michigan } & 1.4 \\ \text { New Hampshire } & 3.3 & \text { Minnesota } & 6.0 \\ \text { New Jersey } & 2.2 & \text { Missouri } & -0.8 \\ \text { New York } & -1.6 & \text { Nebraska } & 7.9 \\ \text { Pennsylvania } & 3.5 & \text { North Dakota } & 4.4 \\ \text { Rhode Island } & 6.5 & \text { Ohio } & 2.3 \\ \text { Vermont } & 5.6 & \text { South Dakota } & 11.9 \\ \text { Illinois } & 2.0 & \text { Wisconsin } & -1.0 \\ \text { Indiana } & 1.9 & & \\ \hline \end{array}\)
